Equity method investments - Schedule of Equity Method Investments (Details) - USD ($) $ in Millions	Nov. 30, 2023	Aug. 31, 2023
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 3,400	$ 3,497
Cencora
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 2,430	$ 2,534
Ownership percentage	15.30%	15.90%
Others
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 970	$ 963
Others | Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage	8.00%	8.00%
Others | Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%
Total
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 3,400	$ 3,497